Wood veneers are very thin and often times damage results in replacement of the veneer.
Interior maintenance can require diverse and specialized skills such as upholstery, avionics, and mechanical.
Interior photo of a Ford Tri-Motor.
Photo credit: Photo provided by Tim Kern.
Attention to detail is key when cleaning and maintaining leather seats and fine carpets such as in this Lear 45.
Interior shops require craftsmen with specialized skills such as seat upholstery.
Photo credit: Photo provided by Tim Kern
Seemingly unimportant looking details such as proper replacement of insulation must receive the same proper treatment as anything else on the aircraft.
Photo credit: Photo provided by Tim Kern
Care, cleaning and maintenance of interiors — seats, carpets, and furniture — is something of a different world. Where airframes, avionics, props, and power all have detailed maintenance instructions and procedures, we’re often on our own when it comes to the part of the airplane our most-important clients see every day. Asking experts — suppliers and maintainers — how to keep interior components in good shape is pretty much the only way to get decent answers.
As with most things aviation, interior maintenance should follow the No. 1 rule for safe flight: Never let a bad trend continue. Whether it’s a spill, an ink spot, a crack in the leather, a loose seat track, a tiny water leak at the faucet, or a cabinet that shakes, waiting will not make the ultimate fix any easier.
Having fussy crews is a real blessing here, but cockpit crews rarely concern themselves with things that don’t make the aircraft fly (or not fly). Cabin crews need to be cultivated and trained — by us — so that they keep us informed of those little squawks, before they become expensive ones.
Routine cleaning, vacuuming, and spot cleaning, is the first line of defense. Ink, once dry, is difficult to remove; a quick look after every flight is your only recourse; and an “ink stick” will get rid of the ink, if applied in time. Vacuuming after every flight will preserve the carpet, help find trouble, and save time in the long run. If your aircraft is one that follows best practices and keeps a spare set of carpets, you’ll spend a lot less time cleaning the ones in the aircraft than you will changing them.
Care and cleaning
Tariq Deir, director of operations for Jet Connections at the London Oxford Airport, offers the following advice, “When steam cleaning the carpet while it is still installed on the airframe, it is difficult to judge how much water is being retained; the risk of rust or corrosion becomes much higher. We recommend either waiting for the aircraft to go into maintenance, where we can perform a full carpet shampoo with steam cleaners and detergent, and give sufficient time for the carpet to fully dry. If the carpet cannot be removed, we shampoo the carpet by hand using an enzyme-based product that organically breaks down soil and stains. This allows our team to control exactly how much liquid is applied to an area, whilst taking a minimal amount of solution on board the airframe.”
Deir goes on to say, “Corrosion is very difficult to spot and is commonly caused by moisture retention. After a spillage or spot stain, the crew may panic and use any nearby liquid-based substance to remove the stain. This results in the carpet’s absorbing far too much of the liquid. We recommend using a foam-based germicidal cleaner, sprayed directly on the infected area; it lifts the stain from the carpet fibers, where the stain can be slowly wiped away with a plain towel. This results in minimal or no water retention.”
General wear and tear
Aircraft carpet can cost $2,000 per square yard, and Deir notes that “the most common cause for carpet replacement is the general wear and tear in high traffic areas, such as the entry steps and areas around the galley. I would recommend either cutting out a number of mats from the same material as the carpet and placing them in such areas, or buying a number of decorative rugs. Area rugs are intended to absorb the bulk of the wear and the dirt — and they do. Replacing a mat or rug is inexpensive vs. a whole carpet; as a bonus, it requires no downtime.” He added that you might consider a similar strategy for couches and chairs, using covers and pads where possible.
Deir warns that uninformed or inattentive crew can contribute to the problem: “Other hidden surprises are floorboard deterioration or even floor beam cracks, results of carrying a heavy load or perhaps storing it in an area not best suited for such weight. Age also plays a common factor along with metal fatigue and dissimilar metal contact, all of which can only be revealed once the carpet, panels, etc., have been removed.”
Leather, tough as it is, is vulnerable to light, heat, dry air, water, and even some things we don’t often notice, like certain perfumes. The key is to make frequent and careful inspections, “treat” only when necessary, and clean as unobtrusively as possible — and at least daily with a clean dry cloth. If leather dries out (particularly likely near windows or air conditioning outlets), it can crack and finally split. It’s good to encourage the use of protective coverings in these areas, and also to encourage keeping window shades drawn whenever possible.
Off the shelf “treatments” can cause more harm than good. A lot more. Leathers are best treated only with whatever is recommended by the supplier, which should include a UV protectant. If leather gets too soft, the stitching can elongate the needle holes; at worst, the stitches can pull out.
Maintenance and repairs
Furniture repairs usually entail scratch removal. Brian Barber, vice president of sales and marketing at Bizjet in Tulsa, OK, says that it is hard to overestimate the delicacy of the work, or the amount of patience required, in polishing the finish of veneers. The veneers are so very thin to begin with that those scratches, assuming they do not penetrate to the adhesive, leave an extremely thin layer of wood between the bottom of the scratch and the substrate. Not removing the full depth of the scratch leaves … a scratch. Going too deep will expose the honeycomb material beneath.
Tony Bailey, vice president of operations at Comlux Aviation Services in Indianapolis, IN, notes that interior work differs from regular airframe, engine, and avionics work in that technicians are homegrown: “There is no special licensing; they’re trained on the job. In our system, we have AMTs and A&Ps; we have avionics specialists. In interiors, [formal aviation-related] training is nonexistent. Then there are specialties: woodworking; finishing; fabrication; upholstery; cabinetmakers; installers — then there are the finish fabricators and finish installers. These all require specialized skills, but there is no formal training available.”
Even unimportant-looking details fulfill important duties, and must receive proper treatment: “It’s important to know what you’re dealing with,” Bailey says. “Sound barriers need to be re-installed exactly right, or you’re just adding weight without any benefit. Get the right parts, the right order, and the right fit.”
So, where does he find qualified workers? “We find them in small shops, or sometimes from the big completion centers.” He adds, “A beautiful thing is an A&P that can do interiors and avionics. These guys can write their own ticket.”
Aircraft interior materials, components, and procedures are not commonly known. “You can hire a local cabinetmaker,” Bailey says, “but the certification and weight restrictions — glues, weights, expansion of parts, especially paperwork — all are so important. Especially with woodwork, you’ll find that gaps change at altitude. Temperatures as well as pressures can change dimensions. Not all veneers will work in all circumstances. Everything matters — even the moisture content of the woods. You need to have all sorts of special skills, and sometimes special tooling.
“It’s not like getting an MRO spec on a particular aircraft, where you get a book with specific instructions,” he says. “Even avionics, which differ more radically, at least have good documentation. But interiors — every single interior is unique to that owner. Five or six airplanes, with sequential serial numbers, will not have the same ‘fit,’ one to the other, even with the same interior components. You may find an aircraft that is set up with, say, a wiring harness that is intended to be used in the future — if you do not know why it’s there, what do you do with it?”
Dier sums, “Assuring the crew takes pride in the fantastic machine they are flying while providing a little TLC, will ensure longevity of an interior.” AMT
Tim Kern is an aviation writer, aircraft builder, and private pilot. He is based in Anderson, IN, and can be reached at firstname.lastname@example.org. The following companies provided information and photos for this article. Jet Connections, www.jetconnections.co.uk; Comlux USA, www.comluxaviation.com; BizJet International, www.bizjet.com; and MJ Aircraft Interiors, www.mjaircraftinteriors.com.